android - 在碰撞 JBox2D android 上销毁 body

Question

我需要在 JBox2D android 游戏中碰撞后摧毁一具尸体。我发现当 body 接触时，JBox2D 世界会被锁定。我想在碰撞后摧毁其中一具尸体。世界解锁后我能接到任何回电吗？我找到了一个选项，可以将 body 添加到数组中以销毁它。但是什么时候摧毁 body ？。我没有在这个游戏中使用 andengine/libgdx。在下面找到我的碰撞监听器类，

private class CollisionListener implements ContactListener {

    @Override
    public void beginContact(Contact contact) {
        Object fixtureA = contact.getFixtureA().getUserData();
        Object fixtureB = contact.getFixtureB().getUserData();
        Body mBodyA = contact.getFixtureA().getBody();
        Body mBodyB = contact.getFixtureB().getBody();
        if (fixtureA instanceof Bullet) {
            destroyBalloonBody(mBodyB);
        }
        if (fixtureB instanceof Bullet) {
            destroyBalloonBody(mBodyA);
        }

    }

    @Override
    public void endContact(Contact contact) {

    }

    @Override
    public void postSolve(Contact contact, ContactImpulse contactImpulse) {

    }

    @Override
    public void preSolve(Contact contact, Manifold manifold) {

    }
}

public void destroyBalloonBody(Body balloon){

//Can i start  a new thread which is having a loop until the world become release for destroying the body
//Or
//Do i need to add the body to a deletionArrayList to destroy it.

}

Answer 1

我认为问题在于您正试图在碰撞回调期间移除主体。

来自 Box2D 手册:

It is tempting to implement game logic that alters the physics world inside a contact callback. For example, you may have a collision that applies damage and try to destroy the associated actor and its rigid body. However, Box2D does not allow you to alter the physics world inside a callback because you might destroy objects that Box2D is currently processing, leading to orphaned pointers.

也就是说，你不应该在碰撞回调中销毁物体。

您应该存储对您希望销毁的物体的引用，并在更新周期后使用世界引用销毁它们。

这是您需要的吗？